Cloning And Analysis Of ZmHDZIV13, ZmHDZIV14Gene Related To Drought Tolerance In Maize And Construction Of Expression Vector

Maize (Zea mays L.) is not only an important food crop, but also an important industrialand feed ingredients. It is of great significance to ensure the development of agriculture andindustry by increasing maize production. Drought is the most important abiotic factors whichaffect the development and production of crops around the world. Many genes involved indrought stress response. By genetic engineering techniques to improve drought tolerance inmaize, maize production can improve in the arid and semi-arid areas.Homeodomain-leucine zipper (HD-Zip) is a class of transcription factors which isunique to plants, it is maked by homeodomain (HD domain) and leucine zipper (LZ) closelylinked with the HD domain carboxy-terminal. HD-Zip transcription factor families arewidely present in many plants, it not only play an important role in higher plants growth,development and morphogenesis but also regulate the response of plants to biotic and abioticstress. The Arabidopsis AtHDG11gene encodes a HD-START transcription factor belongingto the HD-Zip class IV transcription factors family. The expression of AtHDG11can promoteroot elongation and stomatal closure to improve drought resistance. Existing research showsthat overexpression AtHDG11gene in Arabidopsis, tobacco and turf grass showed strongdrought tolerance. There have been identified17Maize HD-Zip IV class transcription factorgenes.Phylogenetic analysis shows that ZmHDZIV13and ZmHDZIV14gene have a higherhomology with AtHDG11. Now the researches about Maize HD-Zip IV gene family is less,mainly is about its expression in different plant tissues and its fuctions in the plant outer skinand hairy roots development, its physiological function, especially the physiological functionunder environmental stress has not been reported.In this research, we got the maize HD-Zip IV gene ZmHDZIV13and ZmHDZIV14full-length cDNA sequence which is homologous to the AtHDG11gene by searching theNCBI database. By RT-PCR and homology cloning method, we cloned these two genes andmake bioinformatics analysis about them. Lastly we construct expression vector.Through the experiments, we obtained the following results:(1) By RT-PCR and homology cloning method, we cloned HD-Zip IV transcription factorfamily gene: ZmHDZIV13and ZmHDZIV14full-length cDNA sequence from the maize genome. Evolutionary analysis showed that: ZmHDZIV13, ZmHDZIV14and ArabidopsisAtHDG11are in the same clade. Protein analysis showed that: ZmHDZIV13andZmHDZIV14gene belong to HD-Zip IV family, and their protein included highly conservedHD domains and extra START domain.(2) Subcellular localization prediction results showed that: the possibility of theZmHDZIV13localized in the nucleus is90.5%, and the possibility of ZmHDZIV14located inthe extracellular is38.5%.(3) The promoter motif search of ZmHDZIV13and ZmHDZIV14showed that there weremotifs related to low temperature, anoxia, salt stress, light, dehydration and others.(4) We constructed CPB-ZmHDZIV13(pCAMBIA3300-35S-ZmHDZIV13-bar) andCPB-ZmHDZIV14(pCAMBIA3300-35S-ZmHDZIV13-bar) plant expression vector, andtransferred the plant expression vector into Agrobacterium tumefaciens LBA4404.